One of the things I made with those damsons was damson cheese. It's very similar to making quince cheese and the result is a malleable paste, a bit tart and great when paired with dry cheese. Start by covering the damsons with water and let them cook until they burst and the flesh and stones have come away from the pulp. Then push everything through a sieve and for every 600 ml of purée add 450 g of granulated sugar. Let the sugar dissolve in a low heat and then increase the heat and let it boil (keep stirring so it doesn't burn) until you scrape the spoon through it and you can see the base of the pan for a few seconds. Finally, pour the mixture into sterilised bowls (I used an old glass mould), let it dry for a few days and that's it!